Surface-gage.



i No. 761,381'.

K PATBNTBD MAY s1, 1904. H. yJ. HJORTH. SURFACE GAQE. APPLIOATION FILED 00'1'110, 1903.

I0 IODEL.

MN. Q

" UNITED STATES:

Patented May 31, 1904. l'

PATIENT ,OFFICE HENRY J. I-IJORTH, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOE TO THOMAS E. OBRIEN, OF* VVATERTOVVN, MASSACHUSETTS, AND

l.MASSACHUSETTS- v 1 JOSEPH F. EATON, OF BOSTON,

` SuRFAC-GA'GE.

sPEoIFIoATroN formmgfpat-'of Letters Patent No. 761,381, dated May 31, 1904.

Application flied Octobei` 16, 1903.

To (LH, 11i/1.0m t may concern:

. Beit known that I, HENRY J. HJORTH, of Cambridge, in the county of Middlesex and State of Massachusetts, have invented 'certain new and useful 'Improvements in Surface- Gages,of which the following is a specification.

This invention relates'to surface-gages;` and the object thereof is to increase the accuracy, durability, and cheapness thereof. For accuracy and non-springing the needle or scratchawl should be supported as rigidly as possible and equally rigid in fall adjustments, Vwhich consideration, it will be observed, visfuliilled by the construction about to be described, such construction also'secu ring the remaining aforesaid objects. as 4will appear.`

Of the accompanying drawings, Figure 1 -represents a perspective view of a surface-gage embodying my invention. Fig. 2 represents a transverse vertical section thereof. Fig. 3 represents a section on line 3 3 of Fig. 2.

The same reference characters indicate the same` parts in all the iigures.

In the drawings, 1 0 isaframe, base, or standard having two flat surfaces 11 12 for seating the instrument on vertical or horizontal surfaces, said frame being formed with vertioai parallel-faced guides 13 13, separated by a recguides laterally in both directions.

lobvious that the slot 15 permits'a wide and quick adjustment of the scratch-awl in `a direction parallel to the guides 13, the clampingholder 17 being also capable of angular adjustment and serving to clamp the scratchfawl iirmly to the slide in anyposition to which the awl has been adjusted. V

In the lower end of the slide 14 is fixed av guide-pin 20, mounted in a suitable guidingaperture 21 in the frame 10, and in the upper Serial No. 176,481. (No model.)

end of the slide is mounted a guide-pin 22, passing through and projecting beyond the upper end of the frame. A spring 23, surrounding 'the pin 22 and let into a socket in the frame,

presses downwardly on the slide 14. The upper end of the pin is screw-threaded at 24 and engaged by a complementally-threaded nut 25, which may have micrometer graduations 26 thereon, as shown in Fig. 1. This nutseats against the upper end of the framell() and upon being turned in the proper direction draws the slide 14 upwardly in its guides. Turning the nut in the opposite .direction allows the spring 23 to press the slide downwardly. By manipulating the nut 25 the needle or awl may be given a fine adjustment through a limited movement of the slide 14 after the awl 18 has been iiXed at approximately y the proper adjustment by moving the clamping-holder 17 along the slide 14 and securing it to the slide. Y The whole construction is eX- tremely rigid and such that no springing of the The shape and relation of the slide 14 and its guides lare such that the needle is supported equally rigidly in any position and the slide is prevented from turning. The pins 2O 22 serve to guide the vertical movements of the slide and prevent lateral displacement thereof frombetween the guides 13.

I claim- 1. A surface-gage comprising a base ory standard formed with opposite guides separated by a space, a slide mounted between said l guides and formedwith a slot elongated longitudinallyof the guides, a needle-holder occupying said slot. and adjustable longitudinally'thereof, said needle-holderprovided with v means for clamping it to the slide at different adjustments, and means for imparting a fine `adjustment'to the slide.

2. A surface-gage comprising a base or stand ard having guides, a slide mounted in said guides and formed with a longitudinal slot, a

' needle-holder adjustable in said slot, a spring interposed between-the slide and standard for impelling the slide in one direction, a screwthreaded member on the slide, and a rotary mounted between said guides, a needle-l1olde1` adjustable on said slide, longitudinal pins at opposite ends of the slide mounted in suitable guides on the standard, one of said pins being threaded, a nut on said threaded pin bearing against the standard, and a spring surrounding said pin and interposed between the slide and standard.

In testimony whereof I have aixed my signature in presence of two witnesses.

HENRY J. HJ'ORTH.

Witnesses:

EDWARD E. BARTLETT, ALZADA E. BARTLETT. 

